Subj : Re: RP400 40-pin connector To : jjlarkin@highlandtechnology.com From : albert@spenarnc.xs4all.nl Date : Thu Aug 15 2024 13:13:57 XPost: sci.electronics.design In article , John Larkin wrote: >I want to use an Raspberry Pi 400 (the keyboard thing) as the >dev/debug system for an RP2040 based product. > >https://www.amazon.com/Raspberry-Computer-Keyboard-Layout-Kabel/dp/B08QCQVWH2 > >It has a 40-pin connector on the back. Various sources say that pins 1 >3 and 5 are either GPIO ports 8 9 and 7 or maybe 2 3 and 4. > >Sometimes the pins are labeled WPI and BCM. Wot's that? > >https://www.amazon.com/Coolwell-Waveshare-Raspberry-Adapter-Expansion/dp/B08RZCR7S8 > >I can fix most mistakes there in software, just by reassigning port >names. But two pins are critical, the SWDIO and SWCLK debug lines out >to a Pi Pico or to the 2040 chip. > >I suspect that on the Pi 400 pin 18 is GPIO5 = SWDIO and pin 22 is >GPIO6 = SWCLK. > >Is that right? Does that actually work? > >I also note that some people also connect the UART tx/rx between the >Pi400 and a Pico for debugging. Should I do that too? Does it help >software development? Is the schematics from the R Pi 400 not available? I have the orangepi 800. The schematics are such that I can trace the connector pins to the soc pins. The RK3399 is fully documented. Mapping the io I can do "das blinken light" on the 26 pin (rp1 compatible) connector, using ciforth (a Forth developed by me). Or light the upper case or numlock leds. > >Thanks! -- Don't praise the day before the evening. One swallow doesn't make spring. You must not say "hey" before you have crossed the bridge. Don't sell the hide of the bear until you shot it. Better one bird in the hand than ten in the air. First gain is a cat purring. - the Wise from Antrim - --- SoupGate-Win32 v1.05 * Origin: Agency HUB, Dunedin - New Zealand | Fido<>Usenet Gateway (3:770/3) .